Scott Walker entered the 2016 presidential race as a conservative who fights and wins. Assuming his announcement isn't totally overshadowed by the Iran deal, the first thing he will have to fight is Donald Trump's hijacking of the GOP nominating contest. Can he win?

The Wisconsin governor is well suited to put an end to the Trumpnado. He offers a blue-collar, can-do conservatism. He appeals to various wings of the party. And most importantly, he can take away immigration as Trump's signature issue.

Walker's tentative embrace of a populist immigration position isn't without political risks. But right now he is the only top-tier presidential candidate who is speaking to the four-fifths of Republicans who are dissatisfied with current immigration levels without derogatory rhetoric about immigrants. The Sen. Jeff Sessions, R-Ala., approach Walker has taken pins the blame for our present immigration problems squarely on big business and big government.

Think Walker is unreliable on immigration? Trump has offered no substance as to what he would do about immigration other than demagogue the issue. His current position is basically an accident, coming after hitting Mitt Romney from the left on immigration after the 2012 presidential election.

Current polling makes it hard to avoid the conclusion that Trump's rise has come partially at Walker's expense. An NBC News/Wall Street Journal poll taken around the time of Trump's announcement had the real estate tycoon at 1 percent and Walker in second place at 17 percent. The latest Monmouth poll has Trump at 13 percent nationally and Walker at 7.

If Walker can recapture the momentum he enjoyed earlier this year after his breakout speech at the Iowa Freedom Summit, it stands to reason he would take votes from The Donald.