Donald Trump has the slightest of leads in Florida, a new poll finds--thanks in part to some to unlikely allies.

Emerson College released a poll of likely voters in Florida on Thursday which finds Trump taking 45 percent and Hillary Clinton right behind him with 44 percent. Gary Johnson pulls 4 percent as the Libertarian candidate while 3 percent are for Green Party candidate Jill Stein.

One of the key’s to Trump’s lead in Florida, which in increasingly looking like a must win state for the Republican nominee, is around a fifth of Bernie Sanders’ supporters are backing him in November.

The poll shows Clinton has not been able to nail down all of Sanders’ old supporters. She gets 62 percent but large segments of them back other candidates as 18 percent of them are for Trump and 17 percent for Stein. Johnson reels in only 2 percent of Sanders’s supporters. After losing to her in the Democratic primaries, where he exceeded most expectations, Sanders has endorsed Clinton.

Both Clinton and Trump face challenges in the final weeks of the campaign, the poll shows. Majorities of Florida voters see both Clinton and Trump as unfavorable, the poll finds. Fifty five percent of those surveyed see Clinton as unfavorable while 43 percent see her favorably. Fifty four percent see Trump as unfavorable while 42 percent view him in a favorable light.

The poll shows a racial divide in Florida as white voters break Trump’s way while minorities prefer Clinton. Trump takes more a third of Hispanic voters in Florida--36 percent--while 59 percent of them back Clinton. The Democrat does better with African-American voters as 77 percent of them support her while 18 percent of them are for Trump.

The poll of 600 likely voters in Florida was taken from October 2 though October 4 and had a margin of error of +/- 3.9 percent.