Romney's got the numbers but is a GOP surprise coming?

Mitt Romney, left, and Rick Santorum are shown campaigning in Puerto Rico. (AP)

With Mitt Romney increasing his lead over Rick Santorum with a victory in Puerto Rico over the weekend, it is likely, that at the very least, Romney will hold his own or increase his lead over Santorum in Tuesday’s Illinois primary.

Mitt Romney now holds a lead of more than 2-1 over Rick Santorum (521-253) -- positioning him as the clear and indeed most likely Republican nominee for president.

But while Romney has won 55% of the delegates thus far – and indeed, it seems clear that neither Santorum on his own or Gingrich will be able to individually stop the former Governor – Romney’s share of the total popular vote cast is well below 45 percent.

Meanwhile, a Washington Post analysis out this morning shows that neither Romney nor Santorum has inspired much commitment from Republican primary voters and neither candidate has cut into the others base of support.

Going forward, it can be expected that the White House will continue to do what it has done recently-- escalate their attacks on all the Republicans and on the Republican Party – which now garners a 10% lower rating than the Democrats in recent polling.

Notwithstanding the Republicans demonstrable weakness, however, the former Massachusetts governor is within striking distance of the president -- with President Obama holding a narrow 4% or less lead in the horse race for President.

Thus, we can expect Mitt Romney and his fellow Republican candidates -- when they get tired of attacking one another – to attack an increasingly unpopular President Obama, whose vulnerability in the polls became clearer and clearer last week.

Indeed, with two-thirds of the electorate saying that the country is headed in the wrong direction, the president's overall job approval is once again below 50%, and he is garnering decidedly negative ratings for his handling of the issue of ever-increasing gas prices.

This suggests that an election that has already been the most negative in American history will become more negative, and arguably less connected to the issues that matter.

To be sure, various GOP leaders have spoken at length about why they hope to resolve their nomination well before their convention opens in Tampa on August 27th to avoid further division and disarray.

And indeed, given the increasingly negative rating for both Mr. Romney and the Party, one can understand why conventional wisdom would suggest that a long drawn out process would be fatal for the Republican party, and Mr. Romney – should he ultimately receive the nomination.

Still, as former Mississippi Governor Haley Barbour said this week, it would not be necessarily bad for the party to be deadlocked going into the Republican Convention.

And while the four leading candidates will almost certainly do everything they can do to resolve things, whether it be through deals, alliances, or horse-trading, there is one other possibility.

And that possibility is that a new candidate can enter the race.

Let us recall how the surprise selection of Sarah Palin as John McCain’s running mate four years ago galvanized a party that had been given up for dead and a campaign that had been given up for lost before the Convention.

However, history suggests that a new candidate-- whether it be Jeb Bush, Chris Christie, or Mitch Daniels -- could well galvanize a party that has become increasingly dispirited and divided.

To be sure, with Governor Romney doing better and better in delegate counts, it is still unlikely that this scenario will be reached, but it is one to take seriously.

Douglas E. Schoen is a political strategist, Fox News contributor, and author of several books including the forthcoming "Hopelessly Divided: The New Crisis in American Politics and What It Means for 2012 and Beyond" (Rowman and Littlefield). Follow Doug on Twitter @DouglasESchoen.