If you think that calls for Clinton to get out of the race are prevalent now, wait until May 20th. Based on earlier projections from the Obama campaign, May 20th will be the day that Obama clinches a majority of the pledged delegates (minus MI and FL). The magic number is 1,627 and Obama's count currently stands at 1,408 (based on MSNBC's projections). Based on the delegate totals that Obama's campaign thinks he will win in the upcoming states (from the memo that the campaign inadvertently sent to a Bloomberg reporter), Obama would pass this milestone on May 20th, after picking up 28 delegates in Oregon and 23 in Kentucky. (NOTE: the Obama campaign's estimates have generally been conservative, they predicted he'd have accumulated 100 fewer delegates at this point than he actually has).
If he does clinch this on May 20th, might Clinton call it quits at that point? Certainly she would be facing increasing calls to get out of the race if she stayed in. In addition, on the 20th, she will likely have won Kentucky but lost Oregon. Thus, she would be able to leave the campaign on a day that she carried a state. The only states voting after the 20th are Puerto Rico and then Montana and South Dakota. She could win Puerto Rico, but she is likely to lose Montana and South Dakota and none of these states will do much to change the delegate count. If she left the race on May 20th, she could do it on a relatively high note and on her own terms, whereas anything after that may make it look like she was forced.
In addition, by May 20th, the Michigan and Florida argument may be largely moot. If you include Michigan and Florida into the equation, then a candidate needs 1,784 to clinch a majority of the pledged delegates. If you give Obama the delegates he won in Florida (67) and the uncommitted delegates from Michigan (55), the projection would put him at 1,771 pledged delegates on May 20th. There are 86 pledged delegates up for grabs in Puerto Rico, Montana, and South Dakota, which means that Obama would easily get the 13 pledged delegates he would need to pass the more difficult milestone (1,784 pledged delegates) even if he lost each remaining state by huge margins.
So, if the delegate count goes as projected, would Clinton get out on May 20th?