Sen. Ted Cruz, R-Texas, announced his bid for the presidency with a tweet early Monday morning, becoming the first major Republican to declare that he is running.

As NPR's Domenico Montanaro reported: "Since bursting onto the scene in 2012 after his GOP primary upset victory against a former Texas lieutenant governor, Cruz has struck out not just against President Obama and Democrats but also Republican leaders."

The Houston Chronicle, which first reported Cruz's imminent announcement on Sunday, said the Texas senator's early focus will be money and the caucuses. The Washington Post Fix blog called Cruz the most underrated candidate in the 2016 field. And Monday, the paper reports:

"Cruz's unrepentant battles against the Obama administration and with leaders of his own party have made him a hero to many conservatives and left him with a powerful national network of small-dollar donors. He will aim to raise $40 million to $50 million for his presidential bid."Advisers said that in coming weeks, as he launches his campaign in states with early caucuses and primaries, Cruz plans to build upon that base of support and cast himself as an uncompromising GOP conservative who has challenged both parties during his short time in Washington."

The Wall Street Journal says: "Mr. Cruz's early presence in the field could pressure other potential candidates to move to the political right on fiscal policy, social issues and on the tactics for pursuing policy goals, particularly among contenders who are trying to establish themselves as the leading conservative alternative to Mr. Bush." The newspaper adds: "But Mr. Cruz's Republican critics say he is too polarizing to be a strong general election candidate."

The American Conservative is less complimentary, saying: "Like many other Republican would-be 2016 candidacies, a Cruz presidential bid doesn't have a realistic chance of succeeding, but then Cruz has already shown during his very brief stint in office that success in achieving tangible results is not what interests him.

"Cruz likes to present himself as the most committed opponent of Obama's agenda, and it makes no difference that his stunts and tactics have had absolutely no success in making a dent in that agenda. What counts for him is demonstrating the intensity of his opposition and pandering to voters that care a lot more about affect than they do about policy substance."

The New York Times notes that while Cruz may be the first Republican candidate to declare his intention, it's certainly likely to be a crowded field in 2016. The newspaper says:

"Mr. Cruz's first challenge is finding a way to stand out in Iowa, where the possible Republican field includes the winners of the last two caucuses, former Gov. Mike Huckabee of Arkansas and former Senator Rick Santorum of Pennsylvania, as well as [Wisconsin Gov. Scott] Walker, Senator Rand Paul of Kentucky, Senator Marco Rubio of Florida, former Gov. Rick Perry of Texas, the neurosurgeon Ben Carson and Gov. Bobby Jindal of Louisiana."

Cruz is expected to make a formal announcement later Monday at Liberty University in Lynchburg, Va.

You can read more of NPR's coverage of this story here:

What You Need To Know About Ted Cruz

5 Reasons Cruz Announced His Candidacy Early

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