Locking front tire under braking?

[JackG]

After a spirited drive or two over the last couple of days, I've noticed that my front right tire wanted to lock up and skid a bit under medium-hard braking.

When just driving normally, it doesn't pull when braking. The rotor seems worn the same amount as the other side, as does the pad. While the car has pulled right just a tiny bit (towards the locking brake) since I bought it a year ago, it was determined that the alignment wasn't causing it, and it probably was the tire. The tires were new, and have been checked out OK.

If I get on the brakes at speed medium-hard, I hear that tire start to skid just a bit, and the pedal starts to pulse a bit after a 1/2 second pause as the ABS kicks in. Harder braking causes just that tire to complain, with ABS doing its job, but only on that front tire. No other ABS or skidding noises from any other corner.

I believe that this has developed over the last few weeks. It's not my imagination; this is definitely something that is different suddenly. Does anyone have a guess what is going on, or do you have a similar repair story to tell?

I'm hoping it's just a sensor or sticking caliper, but so far I have nothing to go on.

Thanks!