RUBIO TO ANNOUNCE? – That's the knowledgeable speculation circulating today.  It appears April 13th may be the day.  From the Miami Herald: 

Marco Rubio has reserved the Freedom Tower in downtown Miami for an undisclosed event April 13, which appears to be a potential, if not likely, spot for Florida’s junior senator to announce his candidacy for president.

A Rubio adviser stressed nothing has been nailed down for any kind of announcement, but the timing makes sense: Likely presidential candidate Rand Paul is expected to make things official April 7, followed by a five-day, five-state announcement tour, so Rubio presumably would not want to share the spotlight during that period.

All-but-announced candidate Jeb Bush appears to be in no rush to shift more formally into campaign mode, but Texas Sen. Ted Cruz made his announcement this week, and Democrat Hillary Clinton is expected to make her campaign announcement in April as well, though nothing has been set.

Rubio, 43, has been preparing for a potential presidential run for at least a year. While behind in most early polls, he has generated considerable buzz as a top-tier contender who offers the party a fresh face, foreign policy experience, charisma and substance.

The Freedom Tower is apparently one of several venues under consideration by Marco Rubio, but it could be an ideal postcard setting to kick off a presidential campaign promoting the promise and greatness of America by the son of Cuban immigrants.

COMMENT:  I believe that Rubio is one of the two guys to watch, the other being Scott Walker.  But Walker has stumbled badly coming out of the gate.  His record in Wisconsin is fine, but he isn't as familiar with national issues as he should be.  He's got to polish up.

Rubio is extremely attractive.  He knows the issues hands-down, speaks fluently and on his feet, has a good voting record, and has youthful vigor.  He has had his stumbles on immigration, but so has Jeb Bush.  There is no such thing as a perfect candidate.  But I believe Rubio is the most attractive candidate running, and would defeat the aging, lying, Hillary Clinton.  And I believe in winning.  There are no silver medals in politics.

March 28, 2015