Any sign of success for the anti-Trump effort and 4 other things to watch for in Tuesday’s primaries

With Republicans badly fractured over Donald Trump’s advance toward the party’s presidential nomination, the GOP will award 150 more delegates Tuesday as voters cast ballots in Michigan, Mississippi, Idaho and Hawaii.

Democrats, meanwhile, head to the polls only in Michigan and Mississippi. The latter is expected to be an easy victory for Hillary Clinton, who has enjoyed wide support from black voters in other Southern states, including Louisiana over the weekend. Michigan has been more hotly contested, with Sanders mounting a concerted effort to chip away at Clinton’s lead in the polls.

Five things to watch for Tuesday night:

Are the mounting attacks on Trump starting to work?

Trump’s mixed performance Saturday – he won Louisiana and Kentucky, but lost Kansas and Maine – slowed his momentum, and one possible reason is the onslaught of new attacks on his candidacy.

He is the strong favorite to win Michigan, Mississippi and Idaho, polls suggest, so a loss – or even a narrow win – in any of those states could be a sign of trouble.

Marco Rubio, the Florida senator who is struggling to remain viable after losing 18 of 20 contests, used the last two debates to assail Trump’s business record, portraying him as a con man trying to scam his way into the White House.

Piling on, Texas Sen. Ted Cruz assailed Trump for refusing to release his tax returns. Cruz has also faulted Trump for failing various tests of conservative purity.

And Mitt Romney, the party’s 2012 nominee for president, has stepped forward as the public face of a panicked Republican establishment pouring millions of dollars into an eleventh-hour ad campaign to convince voters that Trump is a vulgar phony unworthy of the presidency.

What will Michigan portend for pivotal contests ahead in Ohio and Illinois?

The upper Midwest has proved challenging for Trump: Cruz won Iowa, and Rubio took Minnesota.

Michigan should be a good fit for Trump – a Rust Belt manufacturing state where the long, slow decline of industry has embittered many blue-collar voters, his core constituency.

But some of the harshest new attacks spotlight down-on-their-luck Americans who spent tens of thousands of dollars on seminars at the now-defunct Trump University. In fraud lawsuits, they allege that Trump ripped them off.

If that line of attack, along with criticism of Trump’s temperament and profane language, pulls voters away from him in Michigan, wouldn’t it also damage him in the March 15 primaries in nearby Ohio and Illinois?

Conversely, if Trump trounces his rivals in Michigan, the night’s big prize with 59 delegates, is there any stopping him?

Turning to the South, a Trump loss in Mississippi would be a huge setback. He has won all four neighboring states: Alabama, Tennessee, Arkansas and Louisiana. Cruz, whose base is evangelical Christians, had hoped to carry them all.

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Can Cruz affirm his organizational strength in Hawaii?

Caucuses require stronger campaign organizations than primaries, and Cruz has proved the most adept at winning them, starting in Iowa.

Hawaii’s 19 delegates are Tuesday’s smallest prize. But bragging rights can be useful too. If Cruz can win Hawaii, he will have racked up victories in at least seven states, fortifying his case that he is the party’s strongest alternative to Trump.

The Flint factor

No city has received more attention in the Democratic primary than Flint, Mich., where a change in the water supply exposed residents to unsafe amounts of lead. Clinton and Sanders have pounded at the issue, saying the crisis would not have happened in a wealthier city, or one with a majority white population.

Given the focus on Flint, its returns will be closely watched. A victory in the city could provide a helpful political boost, showing Clinton can successfully seize on a hot-button issue or that Sanders can connect with voters in majority-black areas where he’s struggled to find support.

Democratic delegate watch

Recent polls show Clinton leading by double digits in Michigan, making her the likely winner. But the margin of victory could make a big difference in the race to pile up delegates. There are 147 delegates up for grabs in the state, the second-biggest amount so far in the primary season.

If Sanders performs well enough, he could prevent Clinton from pulling too far ahead. But if Clinton has a big win, it could allow her to add significantly to her lead of 195 pledged delegates. Clinton also has 458 superdelegates -- elected officials and party leaders who can choose which candidate to support -- while Sanders has only 22. She leads the overall delegate race 1130 to 499.

Twitter: @chrismegerian, @finneganlat

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