Ohio Governor and Republican U.S. presidential candidate John Kasich speaks at a rally in Columbus, Ohio, March 6, 2016. REUTERS/Aaron Josefczyk

Ohio Gov. John Kasich is gaining ground on Republican presidential front-runner Donald Trump and Texas Sen. Ted Cruz in the Michigan primary as Kasich faces a near must-win in the state Tuesday and Florida Sen. Marco Rubio keeps sinking.

A Monmouth University poll out Monday indicates that Kasich is surging with likely voters in Michigan, which borders his home state. The governor currently holds 21 percent of the vote, just behind Cruz, who has 23 percent. Trump still leads with 36 percent, but Kasich has been picking up momentum lately. Rubio lags far behind with 13 percent. The Monmouth University poll surveyed 402 likely Republican primary voters between March 3 and March 6 and claims a margin of error of plus-or-minus 4.9 percentage points.

The Monmouth University poll is not the only one giving the struggling Kasich campaign a ray of hope. The latest poll of Michigan from American Research Group even suggested Kasich has a slight lead in the state with 33 percent of the vote to Trump's 31 percent, scoring wins among voters over 50 and women. The ARG poll surveyed 400 likely Republican voters March 4 and 5 and claims a margin of error of plus-or-minus 5 percentage points.

Other polls, including the latest CBS News/YouGov poll and NBC/Wall Street Journal/Marist poll, have not been so kind to Kasich, showing him lagging in fourth behind Rubio. Kasich is the only GOP candidate who has not won any state yet.

“From everything I understand, I’ve got a significant rise in the polls here and it looks like we are going to have a pretty good night,” Kasich told supporters Saturday.

The Michigan primary is a key one for Kasich, who currently holds only 37 delegates. Trump has a commanding lead with 387 delegates, followed by Cruz, with 300 delegates, and Rubio, with 151 delegates. If Kasich wins Michigan and the winner-take-all race in Ohio next week, his campaign will suddenly look plausible, especially if Rubio loses Florida the same day .

Meanwhile, the Monmouth University poll is more bad news for Rubio, whose campaign is on life support. Following the Super Saturday primaries and caucuses, in which Rubio failed to win any state, Trump and Cruz have both called on the onetime establishment favorite to drop out of the race.