It's been less than three weeks since I trained my eye on mortgage loan insurers, noting that they have been making an amazing recovery from their near-death experiences during the mortgage crisis. This week, it seems, the sector is rocketing skywards once again -- as Radian Group (RDN 0.88%), MGIC (MTG 0.71%), and even troubled MBIA (MBI -0.65%) experience pleasant highs. Notably, all of these insurers have seen their share values soar by more than 60% since the beginning of the year.

Mortgage insurers took a beating, but are looking victorious
Just surviving the massacre that took place when mortgages began going south is quite a triumph in itself, but these mortgage insurers have proven themselves a resilient bunch -- and not afraid to get scrappy when the need arises.

Radian's stock has been on an upward trajectory since its fourth-quarter results, despite missing on EPS targets. The news that the company more than doubled the value of policies written in 2012 compared to the year previous, along with its low risk-to-capital ratio and comfortable revenue estimate beat has doubtless put smiles on its investors' faces. The insurer has received two analyst upgrades in as many weeks.

Despite a beat on revenue estimates, MGIC reported a net loss for the fourth quarter , though a charge pursuant to a dispute with Freddie Mac was reflected in that number. Nevertheless, the company noted that loan defaults were down, and despite a very high risk-to-capital ratio of 47.8:1, investors rallied when management guaranteed that raising capital when needed would not be a problem.

MBIA has really been kicked around by Bank of America in their ongoing brawl over slimy mortgage-backed securities and MBIA's bid to split its mortgage business from its healthier units, which B of A sued to prevent. Now, bruised-but-not-beaten MBIA has emerged victorious, as the state of New York Supreme Court has upheld the approval by the NY State Insurance Department to allow that business division. After that bit of swell news, MBIA's stock rocketed upwards by more than 24%.

Nowhere to go but up
An improving housing picture has certainly helped these companies make such a great recovery, new home sales shot up to a four-year high this past January. Another helping hand was lent by the Federal Housing Administration, which has been ratcheting up its program of fee increases and rule tightening-- which will, eventually and almost certainly, result in more market share for these three companies.

While the climate is changing in favor of these insurers, the fact that they persevered in the face of daunting headwinds -- writing new business with unflagging vigor and working with regulators to make that happen -- shows real pluck. That kind of attitude is sure to bring them two-bagger status by summer -- and you can quote me on that.