Davis grabbed Rangers second goal after only 10 minutes of play
Rangers resisted a stirring comeback from St Mirren to hang on for victory in an entertaining clash at Ibrox.
Kris Boyd's fizzing drive, his 10th league goal of the season, handed Rangers the lead inside five minutes.
And Steven Davis doubled their advantage five minutes later following a sweeping three-player move.
Saints keeper Mark Howard had a string of fine second-half stops before Franco Miranda set up a tense finale with a lovely finish on 81 minutes.
It was a whirlwind start from Rangers, who threatened to blow their opponents away from the first whistle.
And the home side were ahead with just five minutes on the clock.
A long ball from Pedro Mendes was nodded on by Boyd to Kenny Miller, who teed up the shot for Boyd to rifle home despite goalkeeper Mark Howard getting a touch.
Mendes then had a chance when he met a Miller cross from the right only to see his downward header flash just wide of the goalkeeper's right-hand post.
Instead, it was Davis who claimed Rangers' second after 10 minutes.
Kirk Broadfoot started the move down the right before Davis ran on to a Miller pass and sent an angled drive into the far corner.
Mendes then threaded a lovely ball through to Miller who turned on the edge of the box before seeing his shot deflected narrowly over the bar as Rangers piled on the pressure.
Rangers could have all but secured victory when Mendes turned provider again, this time delivering to the feet of Adam who squandered a great opportunity by screwing high and wide from just inside the box.
Saints were forced to make their first change five minutes before the break when Steven Robb hobbled out of the action and was replaced by Stephen McGinn - who netted the winner against Rangers at Love Street earlier this season.
McGinn may have caught Allan McGregor off guard with a long-range winner the last time the two clubs met but the Rangers goalkeeper easily dealt with a shot from distance within a few minutes of the restart.
Miller then blew an excellent opportunity to increase Rangers' advantage when he seized upon a poor pass back from Miranda to Howard, with the goalkeeper stranded.
But, instead of rolling the ball into a gaping net, the striker took an extra touch and somehow managed to scoop the ball over.
Miller had the chance to make amends when he collected a Davis pass just outside the box and hit the shot well enough only to be denied by a decent parry from Howard.
Then Howard tipped Barry Ferguson's curled shot round the post as Rangers laid siege to the Saints goal.
With nine minutes to go, Miranda ran on to Craig Dargo's cute back-heel to sweep the ball past McGregor and hand Saints a lifeline.
Having been seemingly down and out since the 10th minute, suddenly the Paisley side were back in the game.
And McGregor brilliantly tipped Dargo's direct free-kick away to maintain Rangers lead as Saints threatened to steal a point from the jaws of defeat.
The Buddies caught a whiff of a famous comeback and threw everything at Rangers in the closing minutes.
But the Ibrox men withstood the late assault to claim all three points and cut Celtic's lead at the top of the table to a single point.
Rangers manager Walter Smith:
"We started the game really well with a couple of good finishes. When you do that you've really got to add to it.
"We had two good opportunities at the start of the second half and didn't take them and St Mirren gained confidence from that.
"In the end we were a bit fortunate and Allan McGregor had to make a great save from a free kick to keep the scoreline at 2-1.
"We've had too many games like this recently where we've had opportunities to kill off a game and haven't done so."
St Mirren manager Gus MacPherson:
"I knew this would be a difficult game and after the first 10 minutes it was getting even harder. What do you do when you start a game like that?
"It was going to be a hard day's work for us but credit to them in the second half. I thought they stuck to their task. With the quality Rangers have they were always going to create opportunities and we rode our luck at times.
"We were brave and showed a lot of courage in the second half to still try and get on the ball. It would have been quite easy to hide and and accept it was going to be a defeat."
This page is best viewed in an up-to-date web browser with style sheets (CSS) enabled. While you will be able to view the content of this page in your current browser, you will not be able to get the full visual experience. Please consider upgrading your browser software or enabling style sheets (CSS) if you are able to do so.