Marco Rubio finished a distant fourth with 13 percent. | AP Photo Poll: Rubio a distant fourth, Kasich surging in Michigan

Marco Rubio is in trouble in Michigan, if the latest results from a Monmouth University poll out Monday are any indication.

The Florida senator finished a distant fourth among those likely to vote in Tuesday's Republican primary with just 13 percent, trailing Donald Trump, Ted Cruz and John Kasich. A threshold of 15 percent is necessary to claim any delegates in Michigan.


Trump led the way with 36 percent, followed by 23 percent for Cruz and 21 percent for Kasich, the governor of Ohio who has pinned his hopes both in Michigan and, like Rubio, on his home state's March 15 primary. Ben Carson earned just 1 percent, though his name was read to voters on Thursday only, a day before the retired neurosurgeon formally suspended his campaign. Just 5 percent said they are undecided among those candidates.

About 13 percent said they have already voted early, while 36 percent said they are completely decided on their candidate. Another 29 percent indicated a strong preference, while 9 percent indicated a slight preference and 14 percent said they are undecided about a number of candidates.

Trump has varying levels of support among all income levels, though he is tied with Cruz when it comes to evangelical Christians. Evangelicals make up less than half of the likely electorate Tuesday.

Results shared by Monmouth showed a tightening race over the last several, with Kasich surging nine points in the period between Saturday-Sunday and Thursday-Friday. Trump, meanwhile, fell by seven points in the same time frame.

Rubio is in a similar position in the latest RealClearPolitics average of polling in the state, at 13.4 percent.

Among likely Democratic primary voters, Hillary Clinton holds a 13-point lead over Bernie Sanders — 55 percent to 42 percent, with 49 percent responding that they are completely set on their candidate.

Asked who would do a better job protecting water quality — an important issue in the state given the situation in Flint — 61 percent said they would do equally as well, while 18 percent favored Clinton and 17 percent Sanders.

Monmouth conducted the poll via landlines and cellphones from March 3-6, surveying 402 likely Republican primary voters with a margin of error of plus or minus 4.9 percentage points and 302 likely Democratic primary voters with a margin of error of plus or minus 5.6 percentage points. For both samples, respondents were drawn from a list of registered voters who participated in either the 2012 or 2014 primaries or voted in the last two general elections and indicated that they would vote Tuesday.