Even with no clear candidate waiting in the wings to oppose her, U.S. Sen. Susan Collins has been hauling in record amounts of cash for a re-election campaign in 2020.

The Maine Republican, who will be seeking her fifth term if she decides to run, collected more than $1.5 million in campaign donations in the first quarter of 2019, following her fourth-quarter haul in 2018 of $1.9 million, which broke her previous fundraising record.

Much of that money, federal campaign finance reports show, has come from donors outside of Maine – some of it collected at swanky, invitation-only cocktail parties or receptions, such as an event in April hosted by Loews Corp. executive Andrew Tisch at his home on Park Avenue in Manhattan.

Partygoers were encouraged to donate the maximum of $5,600 to Collins’ campaign to get in the door. Under federal law, individual donors can give a candidate’s campaign $2,800 for both the primary and general election campaign – even without a primary challenger.

Many donors also have their spouses give parallel donations, making each couple worth as much as $11,200.

The Tisch event was part of an effort by the moderate bipartisan No Labels group and was meant help Collins stay in the Senate, according to the invitation signed by Tisch.

“We think her defeat would have a chilling effect on bipartisanship in Washington,” the invitation read.

With nearly $4 million in the bank at the end of March, Collins had the fifth-largest amount of cash on hand among the 31 Senate incumbents seeking re-election in 2020. Collins, who has said she plans to run again but has not made a formal declaration, is among 19 incumbent Republicans who will likely seek re-election.

The pace of donations to her campaign has slipped only slightly since the last quarter of 2018, when she was under close scrutiny for her vote on President Trump’s nomination of Brett Kavanaugh to the U.S. Supreme Court.

In other fundraisers, Collins was the guest of honor at a luncheon in Houston in January hosted by U.S. Sen. John Cornyn, R-Texas, who is also up for re-election in 2020.

Critics of Collins point out that she accepted far more money for her campaign from Texas oil industry executives than she did from Maine people during the first quarter of 2019.

However, it’s not unusual for members of Congress to receive donations from out-of-state contributors. Maine’s two U.S. representatives, Chellie Pingree and Jared Golden, both Democrats up for re-election in 2020 — also collected the bulk of their campaign donations in the first quarter of 2019 from out-of-state donors.

Amy Abbott, the deputy treasurer for Collins’ campaign, said Thursday that the strong financial support from outside of Maine was something the campaign was grateful for and proud of.

“Her national reputation as an effective centrist senator has resulted in her receiving contributions from all 50 states and has led to her being ranked fifth among all senators in cash-on-hand,” Abbott said.

She said the campaign still expects to be outspent overall when PAC and super-PAC spending is factored in.

“Nevertheless, this strong quarter makes us confident that we will have the resources we need next year when the campaign begins in earnest,” Abbott said.

In 2014, Collins breezed to re-election, winning more than 60 percent of the vote against Democratic challenger Shenna Bellows. That year Collins’ campaign spent $5.5 million – more than double the $2.3 million Bellows raised and spent – and ended the race with nearly $1 million still in the bank.

But spending in 2020 will easily eclipse 2014, as Democrats and progressive groups take aim at Collins after she voted to confirm Kavanaugh last year.

Mainers for Accountable Leadership helped run a crowdfunding campaign that raised nearly $4 million for a Democratic nominee to challenge Collins after the Kavanaugh vote last September. However, the crowdfunding effort also fueled donations to Collins from her supporters, her campaign officials have said.

As in 2014, national political action committees and super political action committees, which can spend unlimited amounts of undisclosed cash, are also setting up to target Maine in 2020.

On the left, Mainers for Accountable Leadership will likely throw their support to the Democratic candidate, while on the right, the Maine Way PAC has been formed by the former chief financial officer for the Republican National Committee, Ben Ottenhoff.

Ottenhoff has registered similar PACs in other U.S. Senate races where Republicans could be targeted or vulnerable. The PAC would be a likely conduit for independent expenditures supporting Collins and attacking her opponent in 2020.

Also on the left is the super-PAC American Bridge 21st Century, which has made Collins a primary target for 2020, said Amelia Penniman, the communications director for the PAC’s Senate campaigns, who took aim at Collins’ first-quarter campaign finance reports.

“Susan Collins’ campaign is bankrolled by a who’s who of special interests and out-of-state millionaires – and supported by a laughably small number of Mainers,” Penniman said. “Her commitment to fundraising out of state sends a clear message to Mainers ahead of 2020: Collins has left them behind in pursuit of extending her career in Washington.”

But Collins still enjoys broad support among a cross-section of Maine voters and had the second-highest favorability ratings in a recent Pan-Atlantic poll of 500 voters in March, with 62 percent saying they had a favorable opinion of Collins. Sen. Angus King, an independent, had a favorable rating from 66 percent of respondents.

The poll, which had a 4.4 percent margin of error and a 95 percent confidence level, found that 51 percent of voters would choose Collins in a race between her and Maine House Speaker Sara Gideon, a Democrat. Although Gideon has not said she will run, her name has been among those mentioned as possible opponents to Collins from the left.

The poll found that 29 percent would pick Gideon, while 11 percent said they would select a third-party candidate and another 7 percent were undecided.

Maine Democratic Party Chairwoman Kathleen Marra said in a written statement that Collins’ recent donations suggest she is “cashing in on her decades in Washington, and she’s drawing support from wealthy out-of-state donors and D.C. special interests.”

Marra said the relatively small number of donations from Maine – from about 15 individuals in the first quarter – is not surprising and shows Mainers are done with Collins.

“Voters here are ready for a change and eager to elect a new senator who will represent our values,” she said.

Abbott, with the Collins campaign, said the campaign had not started to solicit donations from Mainers yet, which is typical for Senate campaigns, and why the donations appear lopsided.

“In fact, we have not held a single fundraiser in Maine yet this cycle,” Abbott wrote in an email to the Portland Press Herald. “We will be doing some in-state fundraising later this year, but we will be focused out-of-state for most of 2019.  The reality is, any serious Senate campaign in Maine since the 1980s has received most of its funding from out-of-state sources. “